This invention relates to exhaust systems for scavenging combustion products of an internal combustion engine. Exhaust systems for internal combustion engines are generally comprised of exhaust passageways for routing the combusted gases away from the engine. The passageways of the exhaust system are defined by the components of the exhaust system. The types of components which comprise exhaust systems include but are not limited to sections of exhaust tubing, mufflers, catalytic converters, and manifolds all of which are well known in the art. Most components of exhaust systems are often made of materials, which are susceptible to corrosion.
Water often enters and collects in the passageways of these exhaust systems. This water can be introduced into the passageways in any number of ways. Water vapor is a product of the combustion process of many internal combustion engines. When the exhaust system is cool the water vapor in the combustion products often condenses and collects in the passageways of the exhaust system. Water from the atmosphere also enters the passageways of the exhaust system in inclement weather. This is especially true for exhaust systems that have a vertical passageway adjacent the point where exhaust gases exit the exhaust system. When the internal combustion engine is operated for a substantial period of time the temperature of the components of the exhaust system becomes high enough to evaporate any pooled water within the exhaust system. The water vapor then exits the exhaust system with the combustion gases, leaving the internal passageways of the exhaust system substantially dry. The passageways of the exhaust system remain dry until water enters the exhaust system from the atmosphere or the internal combustion engine is run for a relatively short period of time and water vapor from the combustion process condenses in the passageways.
The pooling of water in the passageways of the exhaust system, which can occur between times when the internal combustion engine is run for a substantial period of time, can cause a number of problems. During the times when water is pooled in the passageway of the exhaust system accelerated corrosion occurs at the places where the water is pooled. Pooled water can also leak from joints between components of the exhaust system and carry with it soot, end products of corrosion and other substances, which leave unsightly deposits on the exterior of the exhaust system. Finally, pooled water, along with the above mentioned soot and other offensive substances, is often sprayed from the exit point of the exhaust system upon initial operation of the internal combustion engine.
Various different exhaust system designs have been utilized in the past in attempts to reduce the pooling of water in the passageways of the exhaust system. Exhaust systems with devices for separating water droplets from the flow of exhaust gases and subsequently diverting those water droplets out of the exhaust system passageways are disclosed in U.S. Pat. Nos. 3,630,030 and 5,348,562. Exhaust systems with structure for draining water from the passageways of the exhaust system are disclosed in U.S. Pat. Nos. 5,321,215 and 5,808,245.
As a result,xe2x80x94an object of the present invention is to provide an exhaust system for an internal combustion engine which reduces the pooling of water in the passageways of the exhaust system. The present invention is a component for an exhaust system for an internal combustion engine, the exhaust system itself, and a vehicle to which the internal combustion engine and the exhaust system is engaged. According to the present invention a component of an exhaust system for an internal combustion engine has an absorbent liner disposed within a passageway defined by the component. The component for the exhaust system may be a muffler, a portion of exhaust tubing, a catalytic converter, or any other component of such an exhaust system in which such an absorbent liner could be disposed.
The absorbent liner of the present invention would be comprised of a material, which absorbs moisture (especially water). Wicking action occurs in the absorbent liner of the present invention such that moisture that is absorbed is drawn away from the point of contact between the absorbent liner and distributed throughout the absorbent liner. The absorbent liner is disposed within the passageways of the exhaust system at a point where water might otherwise pool. As water collects in the exhaust system of the present invention, any water that comes into contact with the absorbent liner is drawn into the absorbent liner until the absorbent liner is saturated. This prevents water from pooling in the area of the passageways of the exhaust system surrounding the absorbent liner until the absorbent liner is saturated. Because the absorbent liner draws moisture away from interior surfaces of the exhaust passageways, the inclusion of the absorbent liner tends to increase the life of the exhaust system by reducing corrosion of the exhaust system. When the internal combustion engine is operated for a substantial period of time, the temperature of the exhaust system, including the absorbent liner, rises substantially. Once the temperature of the exhaust system reaches a certain level any water within the exhaust system, including that contained in the absorbent liner, vaporizes over a period of time and is exhausted with the combustion products. Any water contained within the absorbent liner is also prevented from leaking out of the exhaust system at joints between components of the exhaust system and staining the exterior of the exhaust system. Water contained within the absorbent liner is also held in the liner even as combustion products travel through the exhaust system at substantial flow rates. Upon operation of the internal combustion engine, any water which is contained within the absorbent liner, is, thus, not sprayed from the exit point of the exhaust system as it often would be if it were allowed to pool in the exhaust system. It can thus be seen that the above mentioned object as well as others not mentioned have been met by the present invention.